Acritarcha z osadów kambru wiercenia Okuniew IG 1

Abstract

 Przedstawiono wyniki badań mikroskamieniałości roślinnych z osadów kambru otworu Okuniew IG l(zachodnia część zapadliska podlaskiego). Stwierdzono 11 gatunków z grupy Acritarcha, które opisano wcześniej z innych obszarów. Zespół z Okuniewa porównano z zespołami charakterystycznymi dla osadów kambru poszczególnych regionów platformy wschodnioeuropejskiej. Podano uwagi o dotychczasowych badaniach Acritarcha w Polsce oraz charakterystykę zespołów akrytarchowych z obszaru północno-wschodniej Polski. ACRITARCHA FROM THE CAMBRIAN OF THE BOREHOLE OKUNIEW IG 1 The paper present the results of studies on Cambrian rocks from the borehole Okuniew IG I (western part of the Podlasie Depression). The studies showed the presence of 11 species of plant microfossils of the Acritarcha group, known from core material in other areas. The assemblage from Okuniew is compared with those typical of individual regions of the East-European Platform. The species are described and their stratigraphic and geographic ranges are given in paleontological part of the paper.Some remarks on previous studies on Acritarcha in Poland are given along with the characteristics of the assemblages of NE Poland.In the Okuniew IG 1 borehole column, specific differentiation of Acritarchs is particularly low in the lowermost horizons of the Cambrian and they are entirely missing in the Sabellidites Zone. The species recorded in the Platysolenites Zone are known from coeval rocks in the Podlasie Depression and Łuków – Wisznice Elevation and the lontova horizon in Soviet part of the East-European Platform.In the Mobergella Zone, there occur species appearing for the first time in the Platysolenites Zone and passing to upper zones in this borehole column.Acritarchs found in the Holmia Zone (Table I) are known from coeval strata in NE Poland, the lukati and vergale horizons in Estonia, vergale and rausve horizons in Latvia and vergale horizon in Lithuania and Ukraina.The species found in the Protolenus Zone in the Okuniew IG I borehole column are known from the rausve horizon in Estonia, Latvia and Lithuania and the Acritarcha assemblage found in the Middle Cambrian – from the Lower and Middle Cambrian of Latvia, western Lithuania and the Kaliningrad region.